hosts.cpp   [plain text]

/*
 * Copyright (c) 2000-2001,2003-2004 Apple Computer, Inc. All Rights Reserved.
 * 
 * @APPLE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this
 * file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */


//
// hosts - value-semantics host identifier class
//
#include "hosts.h"
#include <arpa/inet.h>
#include <netdb.h>


namespace Security {
namespace IPPlusPlus {


class NamedHost : public Host::Spec {
public:
    NamedHost(const char *name);
    
    string name() const;
    set<IPAddress> addresses() const;
    
    bool operator == (const NamedHost &other) const
    { return mName == other.mName; }
    
private:
    string mName;
    set<IPAddress> mAddrs;
};


class IPv4NumberHost : public Host::Spec {
public:
    IPv4NumberHost(IPAddress addr) : mAddr(addr) { }
    
    string name() const;
    set<IPAddress> addresses() const;
    
    bool operator == (const IPv4NumberHost &other) const
    { return mAddr == other.mAddr; }
    
private:
    IPAddress mAddr;
};


//
// Host basics
//
Host::Host(const char *form)
{
    //@@@ IPv4 only at this time
    IPAddress addr;
    if (inet_aton(form, &addr))
        mSpec = new IPv4NumberHost(addr);
    else
        mSpec = new NamedHost(form);
}


//
// Compare for equality
//
bool Host::operator == (const Host &other) const
{
    // really silly hack alert: just compare lexicographically by name
    return mSpec ? (name() == other.name()) : !other.mSpec;
}

bool Host::operator < (const Host &other) const
{
    // really silly hack alert: just compare lexicographically by name
    return !mSpec || (other.mSpec && name() < other.name());
}


//
// Compare for subsumption
//
bool Host::operator <= (const Host &other) const
{
    return false;
}


//
// IPv4 address host specs (a single IPv4 address)
//
string IPv4NumberHost::name() const
{
    return mAddr;
}

set<IPAddress> IPv4NumberHost::addresses() const
{
    set<IPAddress> result;
    result.insert(mAddr);
    return result;
}


//
// IPv4 hostname host specs (a set of addresses derived from a name lookup)
// @@@ If we want to support IPv6, this should ALSO contain IPv6 lookup results.
//
NamedHost::NamedHost(const char *name) : mName(name)
{
    //@@@ NOT THREAD SAFE - find another way to do name resolution
    if (hostent *he = gethostbyname(name)) {
        for (char **p = he->h_addr_list; *p; p++)
            mAddrs.insert(*reinterpret_cast<in_addr *>(*p));
        secdebug("ipname", "host %s resolves to %ld address(es)", mName.c_str(), mAddrs.size());
        return;
    }
    UnixError::throwMe(ENOENT);	//@@@ h_errno translation or other source
}

string NamedHost::name() const
{
    return mName;
}

set<IPAddress> NamedHost::addresses() const
{
    return mAddrs;
}


}	// end namespace IPPlusPlus
}	// end namespace Security